Concrete conveying and mixing machine



July 6, 1937. H. WESTBERG ET AL 20,440

CONCRETE commune AND MIXING MACHINE Original Filed June 8, 1932 2 Sheets-Sheet 1 INVENTORS HARRY WEST LAME/V6! Elf'd WWW ATTORNEYS.

'H. WESTBERG ET AL ,4

CONCRETE CONVEYING AND MIXING MACHINE 2 Sheets-Sheet 2 July 6, 1937.

dri inai Fi led June 8, 1952' INVEN TOR. HARRY WEJYDEEG ZH WEZNCZ' l. MC'OMCK BY imam W Ai'TORNEYS.

Reissued July 6, 1937 UNITED STATES 20,440 concas'ra comma am) MIXING momma PATENT OFFICE Original No. 1,953,091, dated April 3, 1934, Serial No. 610,074. June a, 1932.

Application for rcissue my 13, 1935, Serial No. cam

12 Claims. (cl. 83-'-73) This invention relates to a method and means for mixing and conveying plastic materials. In connection with the construction of various structures, particularly with which the use of 5 cementitious material is concerned; as for example, plasters, cements, and concrete, it has been found desirable to' provide means for continuously mixingthe'ingredients oi the cementitlous mass for continuously and directly de- M livering the mixed mass to a'desircd point of application or deposit.

In most instances where an attempt has been made to obtain suchresultsthe materials have been Dre-mixed withwater. This has caused 15 considerable trouble in the transit conduits due to clogging while the machine is in operation, and due to the complete obstruction'of the conduit lines after operation, unless a great deal of care is exercised to clean the lines to prevent 20 hardening or setting 01' the materials;

Broadlyconsidered, the present invention is concerned with a method of, and means mr, conveying-comminuted particles to a remote point by dispersing said particles within a fluid, such 2 asgair, within which and by the action of which fluid and-suitably acting mechanical means th-r material is conveyed to a. desired remote point.

The present invention is specifically character.- ized by providing a method and means for mixv ing the ingredients of a cementitious mass while in a substantially dry state, dispersing the particles within a fluid medium such as air, and thereafter conveying the mixed materials to an outlet nozaleby mechanical and pneumatic-force and sumending action, and then properly and intimately mixing the ingredient particles with water just prior to their discharge from the conveyhzgcmdnihandastheparticles oi wet plas-' ilenntegialareproiectednponthesuriacetobe esoteric-directed into a suitable form or conhim- The M invention can the provlallmotnmixinghopperinto which desired and patrolled :otrelaflvelydzyingredi- 45 eniamaybephcedand'fi'omwhichthesemixed maybewithdmwninmeteredquan- 'timsaidmixingmeteringdevicebeingdismsedadjacenttoaconveyorby which thedrymaterlalswillbeagitatedandimpelled 50 intoa conv ying conduit; Interpooed between the metering device and the mechanical conveyor is a chamber or dome into which air is delivered under pressure, said air acting to mechanically agitate, disperse and suspend the particles of material and to carry it forwardly 5 through the apparatus. The mechanical impelling action of the conveyor is also assisted by the force of air under pressure passing through the conduit and within which the particles are mechanica-lly suspended. The discharge end '01 the conduit is provided with a discharge nozzle within which is incorporated means for insuring that water and the dispersed dry ingredients will commingle and adequately mix as they travel through the nozzle to thoroughly hydrate the particles and will be. projected therefrom in a plastic mass 01' desired consistency and hydration.

The invention is illustrated-by way of examplein the accompanying drawings, in which: 0 Figure 1 is a view in central vertical section and elevation through the conveying and mixing device with which the present invention is concerned.

Fig. 2 is a view intransverse central section through the device as seen on the line 2-2 oi Fig. 1.

Fig. 3 is an enlarged view in. transverse section through the nozzle as seen on the line H of Fig.- 1 and particularly showing the construction 01' the mixing chamber of the nozzle.

Fig, 4 is a view in longitudinal section showing another form of construction of our invention.

Hg. 5 is a view in transverse section through the form. of the device indicated in Fig. 4 as seen onthelinei-ioiFig.4.

Referring more particularly to the form of the invention shown in'Flgures 1 to 3, inclusive, of the drawings, il indicates a hopper through which measured quantities of various ingredients are disposed, such as plaster and'sa'nd used in making wall plaster or mortar or sand, gravel and cement and in making'concrete. The hopper may be of any desired capacityand is preferably formed with inwardly converging side walls surroimding a restricted throat II at its bottom. Disposed transversely of the lower end of the hopper isa cylindrical housing I! into which the hopper nts. This housing is tormedwith oppositeends II and u whichcarrybm'rings "and" into a feed chamber 2|.

through the feed chamber and carriesa screw.

tity of the dry mixed materials will fall into the pocket 20 and fill the same as the valve rotates. Whe'n the valve has rotated to dispose the, pocket 20 in a. position diametrically opposite from the mouth of the hopper, the material will be dropped A drive shaft 22 extends conveyor blade 23. This blade is reduced in diameter at its outer end and projects through a tapered tubular outlet 2! in communication with the end of the chamber 2|. The shaft 22 is provided with a gear 25 which is in mesh with a gear 2| carried upon the trunnion II. The gear 26 is also keyed test drive shaft 21 which may be driven by any suitable source of supply. The

ratio of the gears 25 and 28 with relation to each other is such that the shaft 22 and its conveyor bladewillbedrivenatadesiredrateof speed withrelation to the speed of rotation of the valve l 9 so that the material may be forced from the chamber 2| when the valve I! has rotated to close opening 23 in the wall of the chamber 2| and between it and the housing l2 which encloses the valve. Secured at the outer restricted end of the tubular member 24 is a conduit 29. This may be a rigid pipe-or a flexible hose, as shown in the drawings. The outer end of this conduit is fitted with a nozzle structure 3| which has a cylindrical portion II to which the conduit 2! is secured. The cylinder 3i is enlarged as indicated at 32 to .provide a mixing chamber 33 through which the material is forced and from which it pames into a tapered tubular nozzle portion 34. Mounted withinthemixingchamberllofthenomleisa spiral blade 35 extending forwardly and outwardly into the nozzle portion. This blade will act to impart gyratory movement to the material being forced through the nozzle. It will be evident that considerable mechanical force and'agitation will be imparted to .the granular material as it is fed into the tapered tubular portion 21 and thence into the nozzle. This force will be obtained by the'action of the screw conveyor blade 3!. Additional force is obtained by the action of air delivered from a suitable source of supply through a pipe]! and projected into the chamber 2i and the tubular extension 24 by inclined nozzles 31. It may also be desirable to deliver air to and through the screw shaft 22 from the pipe II through packing 3| .to outlet openings 22'.

In the cylindrical portion 3| of the nozzle is a water connection 39 to which a conduit It may be secured and by which water may be delivered through the baseof the nozzle to mix with the dry material being fed into the nozzle. The connection 3! extends longimdinally within the nozzle and is formed with perforations 39' through which water may be fed to the materials passing through the nozzle. The force of movement of the material is such as to cause the water and material to enter. the mixing chamber 33with considerable violence. This will be increased due to the relatively large diameter of the .chamber 2|.

chamber into which the material under pressure is released and within which the material is the pocket will be filled with the mixed dry materials and will be carried around to the discharge opening 23 where it will be dropped into the feed In order to maintain a tight jointbetween the cylindrical outer surface of the valve l9 and the housing I hit may be desirable to form the bearings l5 and I 6 separately from the ends l3 and M of the housingso that bearings may be adjusted to move the valve to a seated position.

It may also be desirable to cover the valve with I a coating of rubber or other material such as.

indicated at ll in Fig. 2 of the drawings.

when the'dry material is dropped into the chamber 2|; the blade 23 will force the material endwisefsince shaft 22 is being constantly driven through gears 25 and 26 from the drive shaft 21.

. The force imparted to the moving material will be progressively increased as the material is forced into the tubular throat 24 and from the restricted end thereof into the conduit 29. During this time the material will be to an extent agitated and suspended by the air under pressure projected into the mass of material through the nozzles 31 and openings 22', and will be forced through the conduit 39 due to the pneumatic pressure and also the 'fact, that the material may be carried in suspension in the air passing through the conduit.

'throat of member 3| and enters the larger area a, will tend to reduce the velocity of the material and cause it to swirl around within the mixing chamber 33 to be agitated and given a gyratory' movement as it moves longitudinally into the tubular outlet 34 of the nozzle from which it will be projected with considerable force in a suitable stream' or jet; the material then having a desired water content and having been thoroughly mixed ready for use. The force of the jet may be sufilcient to cause the stream to be projected into forms normally inaccessible and out of the way, or it may be used to permit manipulation of the nozzle so' that plastic material may be directly applied to a surface to be covered. In this event attention is directed to the fact that the force of impact of the material with the surface to be covered will tend to compact the plastic material and to insure that the final set product will be of desired hardness and texture.

In the form of the invention shown in Figs. 4 and 5 of the drawings various changes and modiflcations have been made as compared with the structure shown in Figs. 1 to 3 inclusive.

In this type of the device the hopper Ill communicates directly with an open housing l5 through which the materialto be conveyed is delivered, and within -which housing a rotary valve 46 is mounted. This valve is diiferent from formed with a plurality of measuring pockets 41 5 which receive the loose material deposited upon. the rotary valve and which material falls into the pockets as the valve rotates within the open housing 45. The pockets are sealed along the lower half of the circumference of the valve by 10 an arcuate rubber sealing strip 48 which is mounted upon a resilientpacking strip 49 which is held in position'by bolts 50 which pass through the wall of the housing 45. It will be seen by reference 'to Fig. 5 of the drawings, that the 15 lower portion of the housing 45 is arcuate and that it conforms to the general contour of the ber 49 is preferably formed of sheet spring steel so that it may be adjustably positioned with relation to the surface of the valve member 45 by strip is secured at the upper edge of the packing strip 4! upon diametrically opposite sides of the valve. This strip is held in position by bolts 52. Directly in the bottom of the housing 45 is an outlet opening 53 which is of substantially the same area and configuration as that of the mouth of the pockets 41 in the valve 46.

9 an inverted position at thelowermost point in its travel it will discharge the material therein, per? mitting it to fall through a throat 54 into the housing 55. This housing is cylindrical, having 46 and into which housing the material is delivered and from which it is forced by mechanical and pneumatic action.

A spiral agitating screw- 56 is mounted within the housing 55 upon .a shaft 51. This screw is in this reduction of diameter agreeing with a similar reduction of diameter of the end of the housing 55. The shaft 51 is tubular, communicating at one end with a packing structure 58 5 and a pneumatic supply pipe 59. -Adjacent. the

will produce a pneumatic action, tending to eject the material and to force it into the restricted 0 throat 5l, a swell as agitate the material and maintain the restricted throat 6| open. This throat communicates with the. deliveryhose 2! previously described.

5 shaft 51 there is a supply of air into the throat 54 which occurs between the valve housing 45 plete quantity of material falling into the memd and 'at the Sametime tends tof'a tate the-ma: terial within the hopper so that it will be more I that they will not clog du'ringoperation. This 5' supply of air is delivered froma supply pipe Into a relatively large induction pipe 83 or dome cornmunicating with the throat 54- through the side wall thereof. a

Attention isdirectedto the-factthat the pipe 0 62 is shown as introducing the-air into the dome 53 in a direction [at right. angles to the longitudinal axis of the dome 53. The air passing from the dome into the throat 54 will in turn be projectedtransversely of, the vertical path of the valve [9 previously described in that it is cylindrical valve member 46. The packing mem-' the adjusting screws or bolts 50.' A metal guard' It will be evident that when a pocket assumes an axis parallel to the rotating axis of the valve.

0' reduced in diameter towards its forward end andopposite end of the shaft 51 is a plurality of outlet'openings Bl from which the air may pass and and the screw housing -55. I This causes the com- 1 her 55 to 'be subjected to pneumatic pressure thoroughly mixed and so that there will be greater possibility that the pockets will be filled and;-

5 travel of the measured'quantities oi! material which fall from a pocket of the valve and pass by gravity through the throat. The air passing into this throat from the dome will create turbulence sothat the amounts of falling material will be dispersed throughout the volume of incoming air, and will thereby be, to an extent,

Ill may be filled to any desired amount and it is preferable to completely cover the rotary valve 45. -This-valve will be driven through shaft 21 and as-the valve rotates the pockets 4.1 will be filled successively with the material and moved to a position where they will deliver the material to the throat 54 and thereafter into the lower housing 55. At the same time the shaft 51 will be driven through the gears 26 and 25, and this shaft will act through its screw propeller 56 to force the material endwise'andto cause it to move through the throat 6 linto the hose.

Attention is directed to the fact that the throat 54 provides an unrestricted'passageway for the downwardly moving material and air, and that thesuccessive batches of material will encounter the screw conveyor when passing into lower housing 55 and by which member the materials will be thoroughly disseminated within the associated air so that the'm'ixture of materials and air willbe uniform and continuous during its subsequent travel through the apparatus. During all this time air-is being delivered under pressure through thepipe 62' to the throat 54 where it will producea uniform pressure and agitating action upon the material entering the housing 55. An additional supply of airwili be ejected radially and in a direction long'itudinally of the -shaft 51 through the opening 60 adjacent the discharge throat 6|. chanical feed of the screw will be assisted by a pneumatic medium which will act to agitate and disperse the material as well as to suspend and forceit along its path of travel. This arrange- In this manner the mea ment insures that the air entering the throat 54 under pressure will tend to create a pneumatic action upon the entire mass of falling particles of material, thoroughly agitating-and aerating the same, and-thereby create turbulence in the mass of falling material which will disseminate In addition to the supply of air through the.

and mechanically suspend the material particleswithin the fluid medium as they are carried i'orwardly from the zone of turbulence through the machine and to the discharge nozzle. It will thus be evident that by the method here shown in which measured quantities of comminuted materials are successively introduced into a zone of fluid turbulence, and are thereafter carried forwardly with the fluid as it travels downmethod may be continuously practiced. andthat the final product obtained thereby will have a high degree of uniform structural strength.

It has also been noted that, the mass of materlal in the hopper Ill and the housing "will pulsate'at each time a pocket passes to a point to contact with the sealing and packing member 48. This is due to the fact that compressed air will be locked in each of the pockets and will be 'released when the pockets move to a position within the hopper. This released air will find its way upwardly through the mass of material in the hopper and will tend to agitate and settleit.

It will thus be seen that the structures here disclosed provide means for conveniently metering and conveying dry cementitious products and to thereafterdirectly apply or dispose these products as desired while the product is in a plastic or semi-plastic state.

While we have shown the preferred form of our invention as now known to us, it will be understood that various changes may be made in combination, construction, and arrangement of parts by those skilled in'the art without departing from the spirit of our invention as claimed, and it is to be understood that while wehave described our invention as being applicable for use with various'cementitious materials, it is within the scope of the invention to use the device for the mixing and/or conveying of anymaterials which could be moved through a conduit such;

for example, as liquids, dry materials, or plastic material of whatsoever nature.

Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. A mixing and conveying device comprising a hopper into which ingredients are placed, a valve at the bottom of the hopper acting to withdraw successively measured quantities of the mixed ingredients from the hopper, mechanical, feed means to which said measured quantities or ingredients are delivered, means introducing a fluid under pressure to the deviceat a. point between said valve and the mechanical feed means, a conduit through which the-ingredients are forced by said mechanical feed means and said fluid, a-

nozzle in the end of said conduit, means for supplying the water to said nozzle and means for .mixing said ingredients with the water as they.

are forced from the nozzle.

2. A mixing and conveying device comprising a hopper into which ingredients are placed, a valve at the bottom of the hopper acting to withdraw successively measured quantities of the feed means to which said measured quantities of ingredients are delivered, means introducing a fluid under pressure to the device at a .point between said valve and the mechanical feed means, a conduit through which the ingredients are forced by said mechanical feed means and said v fluid, a nozzle in the end of said conduit, means 'for supplying the water to said nozzle, means formixing said ingredients with the waters they are forced from the nozzle, and pneumatic means aiding the mechanical in conveying the material through the conduit.

3. A mixing and conveying device comprising a hopper into which measured quantities of ingredients are placed in a relatively, dry state, a mechanical -valve at;the discharge-end of said hopper for withdrawing measured quantities of the mixed ingredients therefrom, a feed chamber through which said {ingredients are discharged by the valve, a conduit connected to thefeed chamber, a feedscrew within the feed chamber acting to force the mixed ingredients from the at all timesfto provide a pneumatic seal between v the feed chamber and the hopper and a nozzle from which the mixed materials are projected;

4. A conveying device comprising a feed hopper into which comminuted material may be placed, a draw-oft throat at the bottom thereof, 3.

rotary valve normally closing said draw-off throat, the valve being formed with a pocket in its circumferential face to receive material from the hopper and to discharge it through said .throat, a feed screw housing disposed beneath said hopper and communicating with said throat, a conduit communicating with one end of said housing, a feed screw within the housing to force material into and through the conduit, and means creating pneumatic pressure within the throat and between the rotary valve and the feed screw housing whereby material: delivered from the rotary valve to the feed screw will be acted upon'by pneumatic pressure tending to force it along the feed screw and'through the conduit.

5. A mixing and conveying device comprising a hopper into which finely divided material may be placed, an outlet opening at the bottom of said hopper, a pressure chamber below the hopper and with which saidoutlet opening comrjnuni-. cates, a rotary valve within the hopper for closing the outlet opening, said valve being formed with a plurality of pockets in its circumferential face to receive material from 'the hopper and to discharge it through the outlet opening at the bottom thereof, a feed screw housing below the pressure chamber and in communication therewith to receive the material discharged from the hopper and from a pocket of said rotary valve, means delivering air under pressure to 'saidpressure chamber to create pneumatic pressure upon the quantity of material feeding into the feed screw housing, a. feed-screw within said housing to move the material longitudinally thereof, and a conduit through which said material is forced by the mechanical actibn of the feed screw-and ferential face to receive material from the hopper and to discharge it through the outlet jopening at the bottom thereof, a feed screw housing below the pressure chamber and in communication therewith to receive the material discharged from the. hopper .and irom a pocket of said rotary 'ivalve, means delivering airimder pressure to, said pressure chamber to create pneumatic pressure upon the quantity of material feeding into the feed screw housing, a feed screw within said housing to move the material longitudinally thereof, a conduit through which saidmaterial is forced by the mechanical action of the feed livering air to the conduit as the feed screw feeds '70 screw and the pneumatic action of the air delivered to the pressure chamber, and means de-.

material thereinto to aid in'conveying'the same.

- -7. A mixing and conveyingdevicecomprising pockets in its circumferential face and intowhich pockets said material may fall, an outlet opening in the bottom of the hopper and constantly closed by the valve, said outlet opening substantially agreeing in area with the opening.

area of a pocket, a pressure chamber leading from said outlet opening and being of an area substantially equal thereto, a cylindrical feed screw housing beneath the pressure chamber and in communication therewith and into which the quantities of material from the pockets may be successively fed, a conveying screw of an outside diameter substantially equal to that of its housing and extending longitudinally thereof, a conduit in communication with one end thereof, and means for creating air pressure within the pressure chamber and above the material delivered to the conveyor housing whereby said pressure will combine with themechanical feeding action of the screw conveyor to feed the material there'- from. v

8. A mixing and conveying device for finely divided materials comprising a hopper into which the materials may be placed, a rotary valve at the bottom of the hopper and on' which the mass of material rests, pockets formed in the circumferential face of said rotary valve to receive quan- -tities of said material, an opening in the bottom of said hopper constantly sealed oil from the hopper by the rotary valve, said opening being substantially of the same width as the width of thepockets in the valve, a downwardly extending pressure chamber with which said opening communicates, means forsupplying fluid under pressureto said chamber, a screw conveyor housing of greater capacity than the volume of material the pressure chamber, said housing communicating with the hopper through said pressure chamber, the screw conveyor housing being formed at one end with a restricted outlet passageway, a screw conveyor within the housing adapted to receive the quantities of material succesively delivered from the rotary valve and moving them toward the restricted end of thehousing, and a conduit communicating with said restricted end of the housing and through which said material is forced by the combined action of the screw conveyor and the, pneumatic pressure derived from the pressure chamber. 7

9. A mixing and conve i device for finely divided materials comprising a hopper, a cylindrical rotary valve at the bottom of the hopper and of a diameter substantially q l to the width of the hopper and a length substantially equal to the length of the hopper whereby the 'valve will form a floor for the hopper, pockets formed in the circumferential face of said-rotary valve and extending longitudinally thereof to receive a quantity of material, with which the hopper-'is filled, an outlet opening at the bottom of the hopper and of a size and configuration agreeing-with the mouth of one of the pocketsin the rotary valve whereby the contents from one of said pockets may beaiischarged from the hopper through said opening when a pocket is in register therewith, a pressure chamber beneaththe hopper and into which the material (is discharged through said opening, means interposed'between the wall of the hopper and said rotary valve to create "an air-tight seal between the pressure and the hopper, a screw conveyor housto which the material is delivered from the pressure of the chamber, a conveyor screw therein adapted to force the material from one end of the housing, and means for delivering air under --pressure to the pressure chamber whereby the succesive batches of material successively fed to the screw conveyor from the hopper will be forced from the conveyor housing by pneumatic and mechanical action,.

10. A'conveying device comprising a hopper into which comminuted materials are placed, a throat in connection with said hopper, a valve for withdrawing material from the hopper in a metered flow and delivering the same into said eduction throat, a feed housing with which said throat communicates, the throat having a relationship between the valve and the feed housing to permit the materials to n11 directlf from the valve to the feed housing, pneumatic-means for 1 creating a zone of turbulence within said throat and with the air moving in a general direction acting to move the air and materialparticles transversely of its path of travel from the throat,

the housing being formed with an outlet in the path 'of the materials and air moving therethrough, and a conduit in communication therewith andinto which and along which said airand associated particles will be forced to travel by the movement of the'air and the action of the mechanical feed. 1

11. A mixing and conveying device comprising a hopper into which comminuted materials are placed, a throat in, connection with said hopper, a valve for withdrawing material from the hopper in a metered flow and delivering the same into said eduction throat, a feed housing with which said throat communicates, the throat having 'a relationship between the valve and the feed housing to permit the materials to fall directly from the valve to the feed housing, pneumatic means Y for creating a zone ofturbulence within said throat and with the air moving in a general direction transversely of the path of the falling materials whereby dispersion and mechanical p nsion of the particles of falling materials may be brought about as the air and materials pass downwardly into said feed housing, mechanical feed 'means acting to, move the air and material particles transversely of its path of travel from the throat, the housing being formed with an outlet in the path of the materials and air moving therethrough, and a conduit in communicationtherewith and into which and along which said air and associated particles will be forced to travel bythe movement of the air and the action of the mechanical feed, a discharge nozzle at,

the eduction end of said conduit through which the air and the materials in the condition of dis- 01' falling materials whereby the finely divided sired'pressure within the feed throat, synchronous material falling freely trom the valge throughthe driving means for the material valve and last passageway will be disbursed and placed in sus named mechanical means, and a conduit compension'within the air which flows from the pasmunicating with said feed housing and through 5- sageway to the feed housing, mechaniizal means which the suspended materials and air may flow 5 disposed within said feed housing and acting to from the feed housing. feed the air and suspended material inwardly HARRY WES'I'BERG. while limiting the flow of air to maintain a de- LAWRENCE E. McCORMAC'K. 

